"Based upon what she was wearing, we believe it is her," Officer Darin Snapp said.
Police said they have a person in custody, but no charges have been filed yet.
Willoughby was last seen with the father of her children Sunday morning and police are questioning him. Her family said she was with her two children, ages 1 and 3.
"Everybody's been talking about the father of her two sons, but he's in custody on something completely separate. But we will definitely be talking to him, though," Snapp said.
Willoughby's family said her children's father told them that she left the children and went with someone else in another car.
"Essence does not leave her children, even while they were at daycare. She's always calling to make sure they are OK," a family friend, Terri Harrison, said.
Police made contact with the 42-year-old father of her two boys, who has a domestic violence history. The young boys are currently staying with their maternal grandparents.
Police received a ping from a cell phone, possibly belonging to Willoughby, near Interstate 435 and Truman Road and were in the area Tuesday morning investigating.
Up until the find Tuesday there was no sign of the mother, and it was the account of her 3-year-old that had police worried about the woman's safety.
Her boys were dropped off by their father's family members, and the older one had a disturbing description of when he last saw her. Police aren't releasing the details about what the toddler said to family members, but said it really helped give them information about what happened.
"We don't know where she is. The only witness, unfortunately, is her 3-year-old son," Harrison said earlier in the day Tuesday.
"I talked to her on Friday, and she was expressing some concerns about him (the father of her children) then being angry," the missing woman's grandfather, Jesse Frazier, said.
Since authorities said Monday they didn't have enough information to assign a whole squad, the young mother's family and friend spent the day passing out fliers and phone numbers in a frantic search of information that could help police take the next step.
They went door-to-door in places that made sense, stopped people on the street and flagged passing cars.
The effort yielded some useful leads for police to follow, including a car and an address where the boys' father was seen just 12 hours before the search party's arrival.
"People are opening up their doors. They are saying they recognize this girl from the neighborhood, so we are hopeful," Vonda Jackson said.
"We hope that Essence will come home and that she will be fine," Harrison said Monday.
Witnesses told police they saw Willoughby near the wooded area at 38th and Topping and their search of the area lead to the gruesome discovery.
Anyone with information to is asked to call the TIPS Hotline at 816-474-TIPS.
Copyright 2012 KCTV (Meredith Corp.) All rights reserved.
Family: Body found at 38th and Topping is that of missing momSearch for missing mother turns into homicide investigationThose who wish to make contributions to help raise funds for the family and childrenMore>>
Friday, April 18 2014 3:33 PM EDT2014-04-18 19:33:46 GMT
(Courtesy: Kansas City Star)
Kansas City Police Chief Darryl Forte says they have the highway shooter suspect in custody. Police announced last week that they have positively linked 12 shooting incidents that have taken place onMore >
Jackson County Prosecutor Jean Peters Baker announced Friday that she has filed 18 felony charges against a 27-year-old man in connection with a recent spree of shootings on area highways.More >
Friday, April 18 2014 1:23 PM EDT2014-04-18 17:23:58 GMT
A 14-year-old girl told Overland Park police that a man attempted to abduct her while she was waiting at a bus stop.This occurred near West 87th Terrace and Nall Avenue at 8:19 a.m. The girl told policeMore >
A 14-year-old girl told Overland Park police that a man attempted to abduct her while she was waiting at a bus stop.More >
Saturday, April 12 2014 6:07 AM EDT2014-04-12 10:07:09 GMT
An incredible photo snapped Saturday at the iconic Pipeline on Oahu's North Shore is going viral. A mother humpback whale and her calf were cruising just offshore when a set rolled in. J.T. Gray of NorthMore >
An incredible photo snapped Saturday at the iconic Pipeline on Oahu's North Shore is going viral.More >
Friday, April 18 2014 3:32 PM EDT2014-04-18 19:32:09 GMT
An ailing Miley Cyrus has canceled her concert Tuesday night at Sprint Center.The notice came a matter of hours before she was scheduled to go on stage.A concert promoter tells KCTV5 that Cyrus is in theMore >
An ailing Miley Cyrus is no longer in a Kansas City hospital, but posted on her Twitter page Friday morning that she is "sick of waking up to needles."More >
Thursday, April 17 2014 4:43 PM EDT2014-04-17 20:43:50 GMT
Officials with the VA Medical Center in downtown Charleston say a North Charleston man who was initially federally charged with a $525 fine for an $.89 drink refill will instead be given a warning.More >
Officials with the VA Medical Center in downtown Charleston say a North Charleston man who was initially federally charged with a $525 fine for an $.89 drink refill will instead be given a warning. More >
Friday, April 18 2014 12:13 PM EDT2014-04-18 16:13:12 GMT
Chopper5 was over the scene as a man was taken into custody outside a home that police had surrounded Friday morning.Officers were dispatched to the 1100 block of North Bellefontaine Avenue about 9:30More >
Chopper5 was over the scene as a man was taken into custody outside a home that police had surrounded Friday morning.More >
Thursday, April 17 2014 5:59 PM EDT2014-04-17 21:59:41 GMT
Many families celebrate the Easter season with a traditional egg hunt. The same is true for the Cincinnati Zoo's newest family. The Cincinnati Zoo's gorilla family - one-year-old Gladys, Jomo the silverback,More >
Many families celebrate the Easter season with a traditional egg hunt. The same is true for the Cincinnati Zoo's newest family.More >